Unlock instant, AI-driven research and patent intelligence for your innovation.

Method of manufacturing carbon electrode

a manufacturing method and carbon electrode technology, applied in the manufacture of contact members, manufacturing tools, crystal growth processes, etc., can solve the problems of increasing the amount of power supplied, the undesirable properties of pulled single crystals, and the time needed to manufacture single crucibles, etc., to achieve low impurity content and not affected

Active Publication Date: 2011-06-28
SUMCO CORP
View PDF19 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

This approach effectively reduces impurity incorporation, enhancing the quality of fused silica crucibles and semiconductor single crystals by maintaining low impurity concentrations, particularly in Fe, Na, K, Li, Cu, and Ca, thus preventing dislocation and improving crystal yield.

Problems solved by technology

However, there is a possibility that impurities, such as metal, stick to the surface of a formed electrode, and there is a possibility that portions of the electrode consumed during arc discharge may be incorporated into the vitreous silica powder compact under vitrification due to an effect of a generated arc plasma flow or the like.
When such a crucible is used for pulling a semiconductor single crystal, the incorporated impurities are melted in a silicon raw material melt during pulling and incorporated into the single crystal, such that there is a problem in that the properties of the pulled single crystal may be undesirable.
In addition, in the case where the contaminants such as metal are incorporated into the crucible, crystallization occurs from the contaminants, and the generated cristobalite small pieces exfoliate in the semiconductor melt and are incorporated into the single crystal, thereby causing dislocation.
In addition, due to a resent increase in diameter of single crystal and crucibles, the time needed to manufacture a single crucible has increased, and the amount of power supplied has increased, so that the amount of power consumed has also increased.
As a result, the amount of contaminants incorporated into the crucible from the contaminated electrode increases, such that the above-mentioned problems have become more apparent.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method of manufacturing carbon electrode
  • Method of manufacturing carbon electrode
  • Method of manufacturing carbon electrode

Examples

Experimental program
Comparison scheme
Effect test

experimental example 1

[0116]As Experimental Example 1 according to the present invention, the impurity concentration of the front end portion 13a of the carbon electrode 13 which was not subjected to the shaping was measured. Here, a predetermined amount of the electrode front end portion was obtained, and the impurity concentration thereof was measured by a flame photometer for performing quantitative analysis using flame reaction, and an ICP-AES for identifying an element or determining a quantity of the element from an emission spectrum emitted when the element that was subjected to atomization and thermal excitation by inductively coupled plasma is returned to a ground state. The results are shown in Table 1.

[0117]In the table, the unit represents the number of micrograms of an object to be measured from one gram of a sample.

[0118]

TABLE 1ElementNaKLiAlCaFeTiZrMgCrCuMnNiZnCoAnalysisFlameFlameFlameICPICPICPICPICPICPICPICPICPICPICPICPExperimental0.110.110.150.120.020.02 Example 1Experimental0.040.020.12...

experimental examples 2 and 3

[0119]Under the same conditions as Experimental Example 1, the impurity concentration of the front end portion 13a of the carbon electrode 13 right after the electrode grinding step S12 was measured. The results are shown in Table 1.

experimental examples 4 to 6

[0120]Under the same conditions as Experimental Example 1, the impurity concentration of the front end portion 13a of the carbon electrode 13 right after the grinding step S20 was measured. The results are shown in Table 1.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
particle size D50aaaaaaaaaa
diameteraaaaaaaaaa
particle size D50aaaaaaaaaa
Login to View More

Abstract

A method of manufacturing a carbon electrode for melting an object to be melted by arc discharge, includes: a rubbing step of rubbing the surface of the carbon electrode before power is supplied with a rubbing material of the same type as the object to be melted.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to a method of manufacturing a carbon electrode and a method of manufacturing a fused silica crucible, and more particularly, to a technique able to be applied to heating and melting vitreous silica powder by arc discharge for vitrification.[0003]Priority is claimed on Japanese Patent Application No. 2008-248087, filed on Sep. 26, 2008, the content of which is incorporated herein by reference.[0004]2. Description of the Related Art[0005]A fused silica crucible used for pulling single-crystal silicon is manufactured mainly by arc melting. Briefly, this method is a method of manufacturing a fused silica crucible by accumulating a predetermined thickness of vitreous silica powder on an inner surface of a mold made of carbon so as to form a vitreous silica powder compact that is a vitreous silica-deposited layer, providing carbon electrodes above the vitreous silica powder compact, and heating ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(United States)
IPC IPC(8): H01S4/00
CPCC03B19/095H05B7/085C04B41/91C04B35/52C04B41/009C04B41/53Y10T29/49117C04B2235/72Y10T29/49206Y10T29/49204Y10T29/49002C03B20/00C30B15/10
Inventor FUJITA, TAKESHIMORIKAWA, MASAKI
Owner SUMCO CORP